How to cleanly detach port multiplier ( pmp )

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I can write to the delete file in the sysfs node for the scsi disk to cleanly stop the disk and detach the scsi disk driver, but I can find no similar way to delete the ata link, the pmp, the master link to the pmp, and disable the ata port. How are you supposed to disconnect a port multiplier without causing the kernel to go into error recovery because the link went dead and the device vanished?

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